fix: keep scope subdelegation control-only

crates/pod/src/controller.rs

@@ -728,7 +728,7 @@ async fn controller_loop<C, St>(
                 // RUNNING / Paused: the buffer push is the entire
                 // operation; an in-flight turn (or the next
                 // Resume/Run) will drain it at its next
-                // pre_llm_request. IDLE: auto-start a turn so the LLM
+                // pending_history_appends. IDLE: auto-start a turn so the LLM
                 // sees the buffered notification(s) without a human
                 // Run.
                 if shared_state.get_status() == PodStatus::Idle {
@@ -900,11 +900,12 @@ async fn controller_loop<C, St>(
             Method::ListCompletions { .. } => {}
 
             Method::PodEvent(event) => {
-                // Live echo travels through the SystemItem lane: once
+                // For agent-visible PodEvents, live echo travels through the
-                // the interceptor drains the notify buffer, the
+                // SystemItem lane: once the interceptor drains the notify buffer,
-                // typed `SystemItem::PodEvent` lands as a
+                // the typed `SystemItem::PodEvent` lands as a
                 // `LogEntry::SystemItem` entry and the sink forwards it
-                // to clients as `Event::SystemItem`.
+                // to clients as `Event::SystemItem`. Control-plane-only
+                // PodEvents use this same receive path only for side effects.
                 //
                 // (1) system side effects — idempotent and tolerant of
                 // out-of-order delivery (e.g. `TurnEnded` arriving
@@ -916,17 +917,19 @@ async fn controller_loop<C, St>(
                     &self_parent_socket,
                 )
                 .await;
-                // (2) queue the typed event in the notification buffer;
+                // (2) agent-visible events enter the notification/history lane.
-                // the next LLM request will inject it as a typed
+                // Control-plane-only events (currently ScopeSubDelegated)
-                // `SystemItem::PodEvent` via the interceptor drain.
+                // stop after side effects so they do not wake or notify the LLM.
-                pod.push_pod_event_notify(event);
+                if event.should_notify_agent() {
-                // Auto-kick a turn if the Pod is idle so the
+                    pod.push_pod_event_notify(event);
-                // notification is not stranded. Matches the
+                    // Auto-kick a turn if the Pod is idle so the
-                // `Method::Notify` idle path.
+                    // notification is not stranded. Matches the
-                if shared_state.get_status() == PodStatus::Idle {
+                    // `Method::Notify` idle path.
-                    pending = Some(PendingRun::RunForNotification(
+                    if shared_state.get_status() == PodStatus::Idle {
-                        protocol::InvokeKind::PodEvent,
+                        pending = Some(PendingRun::RunForNotification(
-                    ));
+                            protocol::InvokeKind::PodEvent,
+                        ));
+                    }
                 }
             }
         }
@@ -1072,7 +1075,7 @@ where
                     }
                     Some(Method::Notify { message }) => {
                         // Live echo arrives via `Event::SystemItem` once
-                        // the in-flight turn's next `pre_llm_request`
+                        // the in-flight turn's next `pending_history_appends`
                         // drains this entry through the interceptor.
                         notify_buffer.push_notify(message);
                     }
@@ -1093,10 +1096,11 @@ where
                         // to the next main-loop iteration — drop here
                         // would lose the event entirely (children fire
                         // and forget). Apply the side effects inline
-                        // and stage the typed event on the notification
+                        // and, for agent-visible variants, stage the typed
-                        // buffer so the in-flight turn's next
+                        // event on the notification buffer so the in-flight
-                        // `pre_llm_request` surfaces it as a typed
+                        // turn's next `pending_history_appends` surfaces it
-                        // `SystemItem::PodEvent`.
+                        // as a typed `SystemItem::PodEvent`. Control-plane-only
+                        // variants stop after side effects.
                         let self_parent_socket = parent_socket.cloned();
                         crate::ipc::event::apply_event_side_effects(
                             &event,
@@ -1105,7 +1109,9 @@ where
                             &self_parent_socket,
                         )
                         .await;
-                        notify_buffer.push_pod_event(event);
+                        if event.should_notify_agent() {
+                            notify_buffer.push_pod_event(event);
+                        }
                     }
                     None => {
                         let _ = cancel_tx.try_send(());
@@ -1253,6 +1259,7 @@ fn worker_error_code(e: &PodError) -> ErrorCode {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::runtime::dir::SpawnedPodRecord;
     use protocol::PodEvent;
     use protocol::stream::{JsonLineReader, JsonLineWriter};
     use std::time::Duration;
@@ -1490,6 +1497,91 @@ mod tests {
         );
     }
 
+    #[tokio::test]
+    async fn running_scope_sub_delegated_applies_side_effects_without_notify_buffer() {
+        let mut env = make_env().await;
+        env.spawned_registry
+            .add(SpawnedPodRecord {
+                pod_name: "child".into(),
+                socket_path: "/tmp/child.sock".into(),
+                scope_delegated: vec![],
+                callback_address: "/tmp/parent.sock".into(),
+            })
+            .await
+            .expect("seed child record");
+        env._method_tx
+            .send(Method::PodEvent(PodEvent::ScopeSubDelegated {
+                parent_pod: "child".into(),
+                sub_pod: "grandchild".into(),
+                sub_socket: "/tmp/grandchild.sock".into(),
+                scope: vec![],
+            }))
+            .await
+            .expect("send pod event");
+
+        let pod_future = async {
+            tokio::time::sleep(Duration::from_millis(50)).await;
+            Ok::<_, PodError>(PodRunResult::Finished)
+        };
+        let (status, shutdown) = drive_turn(
+            pod_future,
+            &mut env.method_rx,
+            &env.event_tx,
+            &env.cancel_tx,
+            &env.shared_state,
+            &env.notify_buffer,
+            Some(&env.parent_socket_path),
+            "parent",
+            &env.spawned_registry,
+            false,
+        )
+        .await;
+
+        assert_eq!(status, PodStatus::Idle);
+        assert!(!shutdown);
+        assert!(
+            env.spawned_registry.get("grandchild").await.is_some(),
+            "ScopeSubDelegated side effects must still register the grandchild"
+        );
+        assert!(
+            env.notify_buffer.is_empty(),
+            "control-plane-only ScopeSubDelegated must not enter the agent-visible notify buffer"
+        );
+    }
+
+    #[tokio::test]
+    async fn running_visible_pod_event_enters_notify_buffer() {
+        let mut env = make_env().await;
+        env._method_tx
+            .send(Method::PodEvent(PodEvent::TurnEnded {
+                pod_name: "child".into(),
+            }))
+            .await
+            .expect("send pod event");
+
+        let pod_future = async {
+            tokio::time::sleep(Duration::from_millis(50)).await;
+            Ok::<_, PodError>(PodRunResult::Finished)
+        };
+        let (status, shutdown) = drive_turn(
+            pod_future,
+            &mut env.method_rx,
+            &env.event_tx,
+            &env.cancel_tx,
+            &env.shared_state,
+            &env.notify_buffer,
+            Some(&env.parent_socket_path),
+            "parent",
+            &env.spawned_registry,
+            false,
+        )
+        .await;
+
+        assert_eq!(status, PodStatus::Idle);
+        assert!(!shutdown);
+        assert_eq!(env.notify_buffer.len(), 1);
+    }
+
     #[tokio::test]
     async fn compact_method_is_rejected_while_running() {
         let mut env = make_env().await;

crates/pod/src/ipc/event.rs

@@ -6,8 +6,10 @@
 //!
 //! - **Send** a `Method::PodEvent` to the parent socket, fire-and-forget,
 //!   logging failures without blocking the child.
-//! - **Render** a variant into a human-readable string that the parent's
+//! - **Render** agent-visible variants into human-readable strings for the
-//!   LLM sees via the notification buffer.
+//!   parent's notification buffer. Control-plane-only variants may still have
+//!   a renderer for diagnostics, but receive-side classification keeps them
+//!   out of LLM history/context.
 //! - **Apply side effects** on the parent (registry / pod-registry
 //!   updates) so that the receive path is idempotent and tolerant of
 //!   out-of-order delivery.
@@ -52,11 +54,13 @@ pub fn fire_and_forget(socket: Option<PathBuf>, event: PodEvent) {
     });
 }
 
-/// Render a variant into the one-line human-readable string that will
+/// Render a variant into a one-line human-readable string.
-/// be injected into the parent's LLM context as a system message.
 ///
-/// Kept deliberately short — the LLM can always call `ReadPodOutput`
+/// Only events classified by `PodEvent::should_notify_agent` are injected
-/// to fetch more detail if the event summary is not enough.
+/// into the parent's LLM context as system messages; control-plane-only events
+/// keep this renderer for diagnostics/tests. Agent-visible summaries are kept
+/// deliberately short — the LLM can always call `ReadPodOutput` to fetch more
+/// detail if the event summary is not enough.
 pub fn render_event(event: &PodEvent) -> String {
     match event {
         PodEvent::TurnEnded { pod_name } => {

crates/pod/src/ipc/notify_buffer.rs

@@ -11,8 +11,9 @@
 //! persistent history.
 //!
 //! This is the **single lane** for "system messages produced by Pod
-//! state that should land in the next LLM request": Notify, PodEvent,
+//! state that should land in the next LLM request": Notify,
-//! and any future `<system-reminder>` injection all ride this queue.
+//! agent-visible PodEvent variants, and any future `<system-reminder>`
+//! injection all ride this queue.
 //! Per `tickets/notify-history-persist.md` and `AGENTS.md` (LLM
 //! context の加工原則), there is **no** "transient, history-skipping"
 //! lane — everything injected into a request is also committed to

crates/pod/src/pod.rs

@@ -1081,8 +1081,7 @@ impl<C: LlmClient, St: Store> Pod<C, St> {
         }
     }
 
-    /// Push a `Method::Notify` (or rendered `Method::PodEvent`) entry
+    /// Push a `Method::Notify` entry onto the pending buffer.
-    /// onto the pending buffer.
     ///
     /// The notification will be appended to `worker.history` as an
     /// `Item::system_message` just before the next LLM request, via
@@ -1092,8 +1091,9 @@ impl<C: LlmClient, St: Store> Pod<C, St> {
         self.pending_notifies.push_notify(message);
     }
 
-    /// Push a typed `PodEvent` entry onto the pending buffer.
+    /// Push an agent-visible typed `PodEvent` entry onto the pending buffer.
     ///
+    /// Callers must classify control-plane-only PodEvents before invoking this.
     /// Same lifecycle as [`push_notify`](Self::push_notify) but
     /// preserves the typed `PodEvent` payload so the IPC layer can
     /// emit `SystemItem::PodEvent { event, body }` with structured

crates/pod/tests/controller_test.rs

@@ -971,6 +971,54 @@ async fn pod_event_turn_ended_while_idle_auto_starts_turn_and_injects_system_mes
     );
 }
 
+#[tokio::test]
+async fn pod_event_scope_sub_delegated_while_idle_stays_control_plane_only() {
+    let client = MockClient::new(simple_text_events());
+    let client_for_assert = client.clone();
+    let pod = make_pod(client).await;
+    let handle = spawn_controller(pod).await;
+
+    handle
+        .send(Method::PodEvent(protocol::PodEvent::ScopeSubDelegated {
+            parent_pod: "child".into(),
+            sub_pod: "grandchild".into(),
+            sub_socket: "/tmp/grandchild.sock".into(),
+            scope: vec![],
+        }))
+        .await
+        .unwrap();
+
+    tokio::time::sleep(std::time::Duration::from_millis(100)).await;
+
+    assert_eq!(
+        handle.shared_state.get_status(),
+        PodStatus::Idle,
+        "control-plane ScopeSubDelegated must not auto-start the parent LLM"
+    );
+    assert!(
+        client_for_assert.captured_requests().is_empty(),
+        "ScopeSubDelegated must not issue an LLM request"
+    );
+
+    let (entries, _) = handle.sink.subscribe_with_snapshot();
+    let saw_scope_event_in_mirror = entries.iter().any(|entry| {
+        matches!(
+            entry,
+            session_store::LogEntry::SystemItem {
+                item: session_store::SystemItem::PodEvent {
+                    event: protocol::PodEvent::ScopeSubDelegated { .. },
+                    ..
+                },
+                ..
+            }
+        )
+    });
+    assert!(
+        !saw_scope_event_in_mirror,
+        "ScopeSubDelegated must not create an agent-visible SystemItem::PodEvent; mirror = {entries:?}"
+    );
+}
+
 #[tokio::test]
 async fn notify_while_running_does_not_emit_already_running_error() {
     let client = MockClient::new(simple_text_events());

crates/protocol/src/lib.rs

@@ -73,9 +73,10 @@ pub enum Method {
 /// Typed lifecycle events sent from a child Pod to its parent.
 ///
 /// Delivered as `Method::PodEvent` over the parent's Unix socket. The
-/// parent Controller applies variant-specific side effects (registry /
+/// parent Controller always applies variant-specific side effects
-/// pod-registry updates) and renders a human-readable string that is
+/// (registry / pod-registry updates). Agent-visible variants are also
-/// injected into the parent's LLM context via the notification buffer.
+/// queued into the notification buffer; control-plane-only variants are
+/// not injected into the parent's LLM context.
 ///
 /// Transport is fire-and-forget; receivers must tolerate out-of-order
 /// delivery (e.g. `TurnEnded` arriving after `ShutDown` for the same
@@ -98,6 +99,9 @@ pub enum PodEvent {
 
     /// Child sub-delegated scope to a grandchild Pod via `SpawnPod`.
     ///
+    /// Control-plane only: receivers apply registry side effects and
+    /// propagate upward, but do not expose this as an agent notification.
+    ///
     /// The parent uses this to add the grandchild to its own
     /// `spawned_pods.json` so it can manage the grandchild directly
     /// even if the intermediate child dies. The parent then re-fires
@@ -115,6 +119,22 @@ pub enum PodEvent {
     },
 }
 
+impl PodEvent {
+    /// Whether this event should become an agent-visible notification/history item.
+    ///
+    /// Control-plane-only events still travel over the same wire enum and still
+    /// run receiver side effects, but they must not wake the parent LLM or enter
+    /// the notification buffer.
+    pub fn should_notify_agent(&self) -> bool {
+        match self {
+            PodEvent::TurnEnded { .. } | PodEvent::Errored { .. } | PodEvent::ShutDown { .. } => {
+                true
+            }
+            PodEvent::ScopeSubDelegated { .. } => false,
+        }
+    }
+}
+
 // ---------------------------------------------------------------------------
 // Segment — typed pieces of a user submission
 // ---------------------------------------------------------------------------
@@ -1209,6 +1229,38 @@ mod tests {
         ));
     }
 
+    #[test]
+    fn pod_event_agent_notification_classification() {
+        assert!(
+            PodEvent::TurnEnded {
+                pod_name: "child".into()
+            }
+            .should_notify_agent()
+        );
+        assert!(
+            PodEvent::Errored {
+                pod_name: "child".into(),
+                message: "boom".into()
+            }
+            .should_notify_agent()
+        );
+        assert!(
+            PodEvent::ShutDown {
+                pod_name: "child".into()
+            }
+            .should_notify_agent()
+        );
+        assert!(
+            !PodEvent::ScopeSubDelegated {
+                parent_pod: "child".into(),
+                sub_pod: "grandchild".into(),
+                sub_socket: "/tmp/grandchild.sock".into(),
+                scope: vec![],
+            }
+            .should_notify_agent()
+        );
+    }
+
     #[test]
     fn method_pod_event_scope_sub_delegated_roundtrip() {
         let method = Method::PodEvent(PodEvent::ScopeSubDelegated {